git pre-commit hook to check R scripts with lintr via littler

git-hook-lintr.r

suppressMessages(library(lintr))

files <- commandArgs(trailingOnly = T)

messages <- function(file) {
    result <- lint(file)
    print(result)
    return(length(result))
}

msgs <- sapply(files, messages)

if (sum(msgs) > 0) {
    q(status = 1)
}

git-hook-lintr.sh

#!/bin/bash

if git rev-parse --verify HEAD &> /dev/null ; then
  against=HEAD
else
  against=4b825dc642cb6eb9a060e54bf8d69288fbee4904
fi

files=$(
  git diff-index --cached --name-only $against |
    grep -E '\.[rR]$'
)

if [[ -n $files ]] ; then
  if ! command -v Rscript &> /dev/null ; then
    echo -e "\e[1m\e[33m[warn]\e[0m \e[1mRscript\e[0m not installed" >&2
    exit 0
  fi

  if ! Rscript --vanilla -e 'library(lintr)' &> /dev/null ; then
    echo -e "\e[1m\e[33m[warn]\e[0m R package \e[1mlintr\e[0m not installed" >&2
    exit 0
  fi
fi

for file in $files ; do
  tmp_lintr=$(mktemp)
  git show ":$file" > "$tmp_lintr"
  Rscript --vanilla git-hook-lintr.r "$tmp_lintr" || exit 1
  rm -f "$tmp_lintr"
done

Requires the following R packages:

• littler
• lintr